i suspect that it's probably a combination of three things:

1) reliability is hard when on a power budget. if power was free, they'd just always be looking to renegotiate, but since power is limited, they probably are very miserly about this process which leads to getting stuck in states that require power cycling to force retries.

2) interoperability is hard with open standards, especially old standards that are complicated.

3) open standards come with limitations that sometimes cannot be worked around. (this is where i'm surprised apple hasn't just cheated as they usually do when open standards result in ux they find unacceptable, this leads me to believe the problem itself, of distributed consensus between multiple wireless low power devices with potentially noisy links, is actually very hard)

when you think about it, the technology behind wireless earbuds is nothing short of astounding. they're little battery operated wireless two node compute clusters that can literally fit in your ears, stream audio and maintain nearly perfect synchronization when rendering that audio in the most absolute basic use case.